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00:30Sparrows in South Africa, like all sparrows, they eat pretty well anything, insects, fruit
00:44and particularly seeds, and they convert that diet into their own flesh, which is the richest
00:50of all foods, meat, so they themselves are much hunted.
00:56A falcon is also looking for a meal.
01:22And it has one.
01:25Music
01:51Meat is such a rich food
01:53that a falcon need only kill once a day to sustain itself,
01:58so there's plenty of time for sitting around on the perch.
02:01Nice work, if you can get it.
02:03But getting it is not necessarily all that easy.
02:08This hillside in New Zealand may look bare,
02:12but in fact I'm sitting in the middle of an immense, active colony of shearwaters.
02:18The adults at the moment are out at sea fishing,
02:21but these are their burrows,
02:24and inside almost every one there's a fat, juicy chick.
02:31And this bird knows it.
02:34This is a parrot, a kea,
02:37but not the sort of parrot that's content just with fruit and nut.
02:43Its beak can certainly cope with such things,
02:46but it can also give a bite that kills.
02:51The keas tour the shearwaters' burrows, listening.
03:06They've heard something.
03:08A shearwater chick is moving in its underground nest chamber.
03:21But the tunnel is too narrow for them.
03:26If they want the chick, they will have to dig for it.
03:52Keas became meat-eaters relatively recently
03:56and have no special adaptations to help them find their victims.
04:00But other birds took to eating meat much earlier,
04:04and they have some highly sophisticated ways of locating their targets.
04:11The great grey owl hunts in the Arctic.
04:15In the summer, it scarcely gets dark,
04:17but the owl's prey is in any case largely invisible,
04:20for it's hidden beneath the snow.
04:28Like the kea, the owl listens for its victims.
04:32But its hearing is many times more sensitive than the kea's,
04:36and ten times better than the owl's.
04:39The feathered discs on either side of its face act like ear trumpets.
04:43Each shields the ear on one side from sound coming from the other,
04:47so the owl can scan the landscape in stereo.
04:52It's detected a faint rustle beneath the snow, made by lemming.
05:05The owl has no idea what's going on,
05:08but it can hear the sound coming from the other side.
05:12A faint rustle beneath the snow, made by lemming.
05:36Invisibility was insufficient protection for the lemming.
05:42The great grey owl's extraordinary hearing enables it to hunt the year round,
05:46even through the Arctic winter, when it's dark for weeks on end.
05:50Elsewhere, other owls locate their prey with a different sense.
05:54Vision.
05:56The bigger the eye, the more light it gathers,
05:59so the better it functions at very low light levels.
06:02These eyes are so big that they can't even revolve in their sockets.
06:06They belong to a scops owl.
06:13They're sensitive to shape, rather than colour,
06:16so a scops owl sees a soot and whitewash world,
06:20but a world that most other birds would find impenetrably dark.
06:34Without colour, its movement is limited.
06:39Without colour, it's movement that betrays the presence of prey.
07:00A spider, quite big enough and succulent enough
07:04to provide a snack for a scops.
07:08And that is what it will be if it moves.
07:39Daytime hunters, like these buzzards, have vision of a different kind.
07:49During the breeding season, they feed mainly on young rabbits.
07:56If there's plenty of light, an eye can become virtually a telescope,
08:00and buzzards can spot a rabbit from over a mile away if it moves.
08:09They also see it in full colour.
08:12With such acute distant vision,
08:15a buzzard can keep a great area under constant surveillance
08:19without moving from its perch.
08:22Rabbits feeding beside their warren.
08:25They would be unwise to venture far from their holes.
08:30The buzzard has detected a chance and is in the air.
08:35From 300 feet above the ground, it can see each rabbit very clearly.
08:40The buzzard has detected a chance and is in the air.
08:43From 300 feet above the ground, it can see each rabbit very clearly.
09:11BIRDS CHIRP
09:31No luck this time for the buzzard.
09:36The great majority of a buzzard's attacks are failures,
09:39but the energy spent on an attempt such as this was not great,
09:42and the wind carries it back aloft.
09:51The kestrel, little more than half the size of the buzzard.
09:55It seeks much smaller prey, voles.
09:58Its colour vision is also excellent, better indeed than ours,
10:02for it spans a greater range of the spectrum,
10:04extending into the ultraviolet.
10:06So the blue of the sea around the Cornish coast
10:09appears much more intense to a kestrel than it does to us.
10:14For a long time, no-one could understand how,
10:17or indeed if, that might help it to hunt.
10:20Now we're beginning to get clues.
10:25The voles a kestrel seeks seldom leave the shelter of their tunnels
10:29through the grass, at least during the day.
10:33They repeatedly mark their tracks with droplets of urine,
10:37and urine in ultraviolet light is very conspicuous.
10:43So, with ultraviolet vision,
10:45the kestrel can see the signposts that the voles can only smell.
10:54As a consequence, the kestrel knows just where to focus its attention.
11:03KESTREL
11:06KESTREL
11:09KESTREL
11:12KESTREL
11:15KESTREL
11:18KESTREL
11:21KESTREL
11:24KESTREL
11:27KESTREL
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11:36KESTREL
11:39KESTREL
11:41And that was a success.
11:45The open skies above the wide plains of Africa.
11:50Vultures.
11:52They also eat meat, but only that which has been slaughtered by others.
11:56They, too, rely on keen eyesight to find their meals.
12:02Their eyes are so acute,
12:04they can keep watch over the plains from more than 1,000 feet up.
12:13The warm columns of air rising from the baking ground
12:17and captured by their broad wings
12:19carries them up to great heights
12:21with very little expenditure of energy on their part.
12:26And supports them there.
12:36They scan the ground beneath them,
12:39but they also keep a sharp eye on one another.
12:57KESTREL
13:00KESTREL
13:02KESTREL
13:04KESTREL
13:06KESTREL
13:08KESTREL
13:10A lappet-faced vulture is on the ground beside a carcass.
13:17Griffin vultures have noticed it and have started to wheel downwards.
13:22Others have already joined the lappet-faced around the kill.
13:29As more birds glide down,
13:31their descent is noticed from miles away in all directions.
13:35And as each bird reacts,
13:37the news that a kill has been discovered
13:40spreads across the network of watchers in the sky.
13:51KESTREL
13:54KESTREL
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14:00KESTREL
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14:06More and more start circling downwards towards the banquet.
14:11KESTREL
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14:43KESTREL
14:46In a few minutes, the carcass is submerged
14:49beneath a dense scrum of struggling birds.
14:55Lacking feathers on their heads and necks,
14:58they do not unduly soil themselves
15:00as they plunge their heads deep into the carcass.
15:05And still more come.
15:09The big cats may make most of the kills on the Serengeti,
15:13but most of the meat produced on the plains
15:16is consumed not by lions and leopards, but by vultures.
15:28To human nostrils, the stench of corruption here is overwhelming.
15:33But these vultures are impervious to it.
15:36They can't sense it.
15:38It was the sharpness of their vision that brought them here.
15:44But there's one bird that, exceptionally,
15:48has an extremely acute sense of smell.
15:53Here in the rainforest of Trinidad,
15:55there's an almost unbroken ceiling of leaves above me.
15:59No bird flying in the sky above that
16:02could possibly see a piece of meat like this
16:05lying on the forest floor.
16:07But this is an extremely smelly,
16:10This is an extremely smelly piece of meat.
16:16Let me hide it.
16:26I can keep watch from a hill that rises above the canopy.
16:31Not a bird in sight.
16:41But there's one. A turkey vulture.
16:44And another.
16:49You can tell it's a turkey vulture because its naked head is not black,
16:53like the other kind of vulture here, but red.
16:56And it's always the turkey vultures that are on the scene first.
17:02The meat I put down is directly under there.
17:06And already, it's less than three quarters of a mile ago,
17:09they're beginning to assemble.
17:13It seems almost unbelievable
17:15that the smell from that small piece of meat
17:18could have drifted up through the forest canopy
17:21and so permeate the air
17:23that it can be detected half a mile away.
17:28And it's equally astonishing
17:30that the birds are able to measure its relative strength
17:33with such accuracy that they can trace it back to its source
17:36simply by sensing in which direction it becomes marginally stronger.
17:42But the turkey vulture is exceptionally well-equipped among birds,
17:46with wide-open nostrils
17:48and extremely well-developed sense organs within them.
18:04It's getting close.
18:06There's something in there somewhere.
18:33There's something in there somewhere.
18:51Got it.
18:53Got it.
19:01Their beaks are quite adequate for tearing off strips of flesh,
19:04and vultures, after all, do not kill the animals that they eat.
19:09But those that do have to have much more powerful weapons.
19:24TAMON
19:31Few animals can survive the grasp of these massive tamons.
19:35They belong to the African crowned eagle.
19:39This bird is huge, nearly three feet long,
19:42and it can kill prey over four times its own weight.
19:47It hunts over the canopy of the East African forest
19:50and seeks particularly monkeys.
19:55Vervet monkeys seldom expose themselves
19:57by venturing into the very highest branches,
20:00so hunting them is not easy.
20:10The eagle has relatively short wings for its great size,
20:14which helps if it has to plunge through the canopy.
20:20TAMON
20:34TAMON
20:40TAMON
20:45TAMON
20:50TAMON
21:10The vervets have a special call
21:12that warns the whole troop that danger threatens from above.
21:20TAMON
21:42It's caught a monkey.
21:50Its mate joins it, and together they return to their nest.
22:21The chick is only a few days old,
22:24too young to tear apart the prey for itself.
22:41It has a lot of growing to do and a huge appetite.
22:45The adults will have to feed it for four months
22:48before it's ready to fly from the nest,
22:50and for nine months after that,
22:52before it's strong enough to hunt for itself.
22:57To keep themselves and their young properly fed,
23:00a pair of crowned eagles need a large hunting ground all to themselves,
23:04so all eagles defend their territories with great vigour.
23:09This one, a sea eagle,
23:11is patrolling a forest-covered coast in Malaysia
23:14along which it fishes every day.
23:18Those that live in the air have to fight in the air,
23:21and eagles do so with their primary weapons, their talons.
23:38TAMON
24:08TAMON
24:39Lake Bergoria in the African Rift Valley,
24:43a soda lake fed by hot volcanic springs.
24:48At first sight, a ferociously inhospitable place,
24:52and indeed it is for most creatures.
24:55But although no fish can live in its tepid, soda-laden waters,
24:59it's nonetheless packed with food for fish eagles.
25:09A million flamingos.
25:12TAMON
25:37The food chain that sustains the meat-eater
25:40could scarcely be shorter than it is here.
25:43Microscopic plants, algae,
25:45that can uniquely tolerate these salty waters
25:48proliferate in the sunshine by the tongue.
25:51Flamingos filter the algae from the water with their beaks,
25:54and vegetable is turned into flesh.
25:57And that flesh is food for eagles.
26:10TAMON
26:34The flamingos have to go into the shallows to drink from a spring
26:38that provides the only fresh water in the lake.
26:41But here they are very vulnerable.
26:46As the eagle approaches, the flamingos stampede into deeper water.
26:50The eagle won't tackle them there
26:52because it has difficulty in lifting anything much bigger than a fish
26:56and carrying it away.
26:58So it can only eat a flamingo in the shallows or on the shore.
27:09TAMON
27:16This concentration of prey is so dense
27:19that pairs of fish eagles have been able to establish themselves
27:22every mile or so around the margins of the lake.
27:26But even this number of hunters
27:28has little effect on the size of the flamingo population.
27:38TAMON
28:09Fish eagles normally snatch fish from the surface of the water.
28:14They don't usually tackle a bird on the wing.
28:17But there is no need to do so here.
28:39TAMON
28:41Now it has to drag its victim to the shore.
28:46TAMON
29:07Few hunters can have a greater concentration of prey
29:11continuously at their disposal.
29:14The flamingos are back in the shallows.
29:22It would be difficult to imagine a more barren hunting territory
29:26than this lava field in the volcanic island of the Galapagos.
29:30But there's a bird that finds its prey even here.
29:35TAMON
29:42Although there's little vegetation on land,
29:45there's quite a lot in the waters around the coast.
29:48And these bizarre lizards, marine iguanas, graze on it.
29:52They can even swim down to the seafloor to do so.
29:55There they are unreachable by hunting birds.
29:59But they come out of the sea onto the rocks to rest and to warm up.
30:04The big ones are too big and strong for a hawk.
30:08The small ones can scuttle away and get safety in one of the cracks.
30:13But the females, particularly at one time of the year, are vulnerable.
30:23The Galapagos hawks know exactly when that is.
30:27It's the breeding season,
30:29when the female iguanas must venture out onto the few sandy beaches
30:32to lay their eggs.
30:35Here they can dig the holes they need.
30:48Hawks all over the island keep watch beside the few beaches.
30:57The Galapagos hawks are the largest group of hawks in the world.
31:02They are the largest group of hawks in the world.
31:06They are the largest group of hawks in the world.
31:10They are the largest group of hawks in the world.
31:14They are the largest group of hawks in the world.
31:18They are the largest group of hawks in the world.
31:23By the time the iguana has finished digging and laying,
31:26she must be tired, so the hawk then has its best chance.
31:31But even so, iguanas can run very fast indeed.
31:53If the iguana can reach the rocks, she will be safe.
32:06This one retreats into the burrow she's only just dug.
32:11She'll have to try and make her escape later.
32:23The outcome is by no means certain.
32:26The iguana is still extremely strong.
32:35But not strong enough.
32:53A number of hawks take advantage of this bounty.
32:58Wounded though it is, this one can still run.
33:09The iguana is still extremely strong.
33:12She'll have to try and make her escape later.
33:15The outcome is by no means certain.
33:18A number of hawks take advantage of this bounty.
33:28The hawk has lost this encounter.
33:31It can't catch an iguana once it's reached its burrow,
33:35even though it might still be able to see it.
33:46But some hawks are specially equipped
33:49for snatching their prey from deep within holes.
33:53This is the African harrier hawk.
34:10Its legs are particularly long.
34:14Even more crucially, they're double-jointed
34:17so that they can bend backwards.
34:19Invaluable when groping in the depths of a nest hole
34:22trying to extract a chick, as this young bird is doing.
34:27The hawk has lost this encounter.
34:30It can't catch an iguana once it's reached its burrow,
34:33even though it might still be able to see it.
34:36The outcome is by no means certain.
34:39A number of hawks take advantage of this bounty.
34:42It can't catch an iguana once it's reached its burrow,
34:45even though it might still be able to see it.
34:48This is the African harrier hawk.
34:57No luck.
34:59But the adult, seeking lizards in the rocks, is more persistent.
35:26This is the African harrier hawk.
35:29It can't catch an iguana once it's reached its burrow,
35:32even though it might still be able to see it.
35:35It can't catch an iguana once it's reached its burrow,
35:38even though it might still be able to see it.
35:41This is the African harrier hawk.
35:44It can't catch an iguana once it's reached its burrow,
35:47even though it might still be able to see it.
35:50This is the African harrier hawk.
35:54It swallows its lizard whole.
36:02This lizard, however, has been caught by a shrike,
36:05a much smaller bird and too small to swallow such prey.
36:09But neither its beak nor its claws are powerful enough
36:12to tear its victim's body apart.
36:15This is the African harrier hawk.
36:18It can't catch an iguana once it's reached its burrow,
36:21to tear its victim's body apart.
36:32The acacias of Africa provide all the hooks and spikes
36:36that such a bird could need for butchery.
36:51BIRDS CHIRP
37:09Prey as small as beetles and as big as stoats are treated this way.
37:14Some of the larger animals are left on their skewers like hung game
37:18so that decay loosens their flesh.
37:20And stalks are sometimes built up in these larders
37:23to last the shrike through hard times.
37:26But often the temptation of fresh meat is irresistible.
37:39The lamagaya actually eats bones,
37:42but breaking up a large skeleton is an even bigger problem.
37:49A lamagaya, hefty though it is,
37:51has not got the beak or claws to do that job.
37:55But, like the shrike, it knows a trick or two.
38:19It doesn't just drop a bone anywhere.
38:23It has its favourite patches of bare rock,
38:26though sometimes its aim is not as good as it might be.
38:42It's getting a few sprinters off this bone.
38:45It can swallow even the sharpest fragment
38:48for its digestive juices are so powerfully acid
38:51that bone dissolves very rapidly.
39:11The greatest prize is the marrow,
39:14and to get that, the big bones have to be well and truly split,
39:18and that takes perseverance.
39:20A lamagaya may have to drop a bone up to 50 times
39:24before it hits rock at just the right angle to split it.
39:37The bodies of other animals provide such rich food
39:40that a bird doesn't need to eat a lot of it,
39:43but getting it, nonetheless, demands not only skill
39:46but often a great deal of effort.
39:51An English wood is full of such food,
39:53but the dense cover makes things difficult.
39:58But there is one bird that specialises in hunting here.
40:02It flies very fast, very low,
40:05and takes its victims by surprise.
40:10This is one of its favourite hunting places,
40:13an old overgrown orchard
40:15where lots of woodland birds come to feed on rotting apples
40:19and the grubs they attract.
40:31A sparrowhawk visits the wood every day
40:34and waits for just the right moment.
40:40CHIRPING
40:58It knows every twist and turn in its approach flight.
41:02It's flown it often enough before,
41:04sometimes two or three times a day.
41:10Its short, rounded wings and long tail
41:13enable it to fly at speed through really narrow gaps.
41:40CHIRPING
41:46Warning calls alert the whole woodland.
41:49CHIRPING
41:56This time it wasn't quick enough
41:58to catch the bird community by surprise.
42:04This hunter is six times heavier than a sparrowhawk.
42:07It's a goshawk, and it hunts not only birds but mammals.
42:13A brown rat.
42:17The goshawk, like the sparrowhawk,
42:19can manoeuvre through the narrow gaps,
42:21but it also has another way of hunting in the woodlands.
42:32It will pursue the rat on foot.
42:37CHIRPING
42:50GASPS
43:08CHIRPING
43:16Even though hunters have a formidable armoury and great skill,
43:20most of their hunting trips, like this one, end in failure.
43:26The coast of Cornwall,
43:28the territory of one of the most highly specialised of all hunting birds.
43:34These are one of its favourite prey, pigeons.
43:39High in the sky, so high it's almost invisible,
43:42a peregrine is watching.
43:56Pigeons fly fast.
43:59The peregrine starts its attack.
44:09Wings drawn back, it's travelling at 200 miles an hour.
44:29Striking its victim with its talons at this speed brings instant death.
44:40The peregrine returns to its nest.
44:44CHIRPING
44:58It has two eager customers for the meat.
45:05An adult peregrine must kill several times a day
45:08if its chicks are to be kept adequately fed.
45:13CHIRPING
45:26Five weeks must pass before the chicks are fully fledged
45:29and ready for their first flight.
45:32They start with somewhat experimental outings,
45:35getting used to the feel of the air in their wings.
45:40Another youngster watches.
45:44CHIRPING
45:49Ten days later and the young birds are feeling confident enough
45:52to tease a passing seagull.
46:05The high-speed aerial pounce,
46:07the killing tactic that is the peregrine's speciality,
46:10takes a lot of learning.
46:13CHIRPING
46:19You have to be able in midair to throw your legs forwards
46:22with talons outstretched,
46:24and your sibling's tail makes a good practice target.
46:34Now three youngsters join together in the game.
46:43They perfect the manoeuvre that launches a dive,
46:46the roll and the pumping of the wings
46:48with which the peregrine generates its unique speed.
47:01Tumbling and rolling, diving and striking,
47:04it may seem like innocent play,
47:06but like so much play,
47:08it's practice for the serious business of adult life.
47:14CHIRPING
47:25And now a lesson for advanced students only.
47:28An adult joins the youngsters, carrying in its talons a pigeon,
47:32wounded but still alive.
47:36And the youngster takes it to make its very first kill.
47:40In a month, it will become the swiftest of all the world's hunters.
47:47But only about a third of the earth is covered by land.
47:51The rest is covered by water of one kind or another.
47:54There's plenty of food there too, of course,
47:56but you have to learn very different techniques
47:59if you're going to go fishing,
48:01as we'll see in the next programme, In The Life Of Birds.
48:10THUNDER RUMBLES
48:12WAVES CRASH
48:20MUSIC PLAYS
48:39MUSIC FADES
49:09MUSIC FADES